Project - Nitrogen Cycle & Low Bioload

[TomK2]

Well, I set up a new 55 gal FW unplanted tank on November 28. I let it filter for 5 days without fish. Then I added a small bioload - 6 zebra danios and four platies (December 3). Initial water parameters recorded (test strip -no kit available yet). After 12 days I begin recording daily or every other day water parameters (aquarium pharmacueticals liquid test kit). Since everything is still 0 - I add 3 more Platies (Dec 15). I now have approximately one inch of fish for each 5 gallons. The fish are fed Tetra Min tropical flakes twice daily, enough so that the food is consumed in two minutes each feeding. No water changes are done for the first 4 weeks. Experiment over when NH3 = 0, NO2 = 0 and NO3 = 5 or greater.

Hypothesis #1 - A tank with low bioload can acquire an adequate biofilter without an Ammonia or nitrite spike. Ammonia and nitrite spikes are only from stocking too fast.

Hypothesis #2 - if #1 is valid, using fish to cycle is not harmful, only impatience hurts fish.


What do you think? How long before the experiment is completed? Do you think it will be possible to get evidence of complete nitrogen cycling (ie: nitrate > 5ppm) without detecting ammonia (NH3 >0.25 test kit limit) or Nitrite (NO2 >0.25 test kit limit)? I tried to follow the nitrogen cycle before using a slow buildup of bioload and missed it, so now I am repeating the experiment with greater vigilance. Anyone ever tried this before?

 

[czcz]

What are your readings now, after 18 days of this experiment? Thanks for documenting here. I look forward to reading your aquarium pages when your site is ready

 

[TomK2]

What are your readings now, after 18 days of this experiment? Thanks for documenting here.

To my surprise, All paremeters are unchanged so far! I find this very encouraging. I looked around for data on the timing of ammonia and nitrite spikes, and could not find much hard data. Most sources indicated that ammonia should spike within 3 to 8 days, and clear by 14-18 days. Then nitrite appears in the second week, and takes 2 plus weeks to clear. Average cycle time about 30 days.

So.... you have people who want to spare the fish the ordeal of ammmonia and nitrite. Fishless cycling with ammonia or decaying food doesn't seem to save any time or aggravation, just spares the fish. Bio-spira seems to spare the fish and save lots of time, all for the cost of about $20 - not much considering what most of us will spend on the hobby - IF you can get some of it.

Now there is me. I want to spare the fish the toxic exposure, but I am not in any hurry. I rather enjoy the slow and low bioload approach, since I have "that new tank feeling" for months instead of days or weeks. My intent is to document a sucessful cycle using fish that does not expose the fish to ammonia or nitrite. Then people will have 3 different methods to start a new tank, and can choose the one that fits thier personality.

I think I did this before years ago. I was patient and slowly stocked a new tank and never detected ammonia . However, I was not very consistent in my testing, and kind of gave in to temptation and doubled the bio-load at about 3 or 4 weeks ( I just HAD TO HAVE those new fish!) and was not diligent in measuring the effects after that. THIS TIME, I am going to see the experiment through. Since the parameters have been so stable, I will probably test some of the levels every other day instead of daily. I figure I am about half way through, just another 3 weeks to go.

 

[TomK2]

I look forward to reading your aquarium pages when your site is ready

Aquarium site is waiting for Santa to drop off a digital camera. The rest of the website was done by scanning my photos. Hopefuly, I will have the technology and the time to get it going in January.

 

[gfink]

Tom,
I also did a very low bioload approach. Here is a post from when I finally got some Nitrites which you can read for more info.
http://www.aquariumadvice.com/viewtopic.php?t=37163

Cycle Summary:
5 zebra danios in a 29 gal
Feeding once a day.
Testing every day or two.

no ammonia for 4-5 weeks so I add two platties to help create some pollution.
Another week or so and very low ammonia shows up. (0.5 ppm I think..see link)
This hangs around for a few days then overnight nitrite spike!(borderline high values..so I do a partial water change) FYI....up to now I have only topped off for evaporation.
A week or so more and moderate nitrites are still around...just a little nitrate.
Stumble across some biospira at my non local fish store and try it.
Overnight cycle is complete. (I was ready to move on after 8-10 weeks)

 

[TomK2]

Fantastic Gfink! Your set up is almost exactly like mine, except in size. I am starting with 55 gallons, but used 6 danios and 7 platies. I found it very interesting that you had ammonia and nitrites appear so late in the process. My thinking was that ammonia has been in the tank since the day I added fish. Nitrogen bacteria are also in the tank. If the bioload is just right, what would be a slow accumulation of ammonia is balanced by an increase in number of nitrogen bacteria. During this time what should be a slow accumulation of nitrites can be dealt with by an icrease in number of those bacteria. End result, ammonia and nitrites zero as nitrates accumulate, just like in a well running established tank. I realize that I would have to continue the method when adding future stock, say one fish a week, to allow the biofilter to keep pace with the bioload.

I am sure that you were thinking just what I am thinking - I got this far without any toxins, this is gonna work! Now I am not so sure. If spikes can occurr as late as 7 weeks, this would explain why I missed them in the past. I think I will keep the experiment going for a few more weeks. I was tempted to start increasing the bioload at 30 days, but now I think I will push that back. Thanks for your input!

 

[PK Tester]

Tom,

Have you ever attempted to "seed" an aquarium?

I have heard from a lot of people they have almost instant cycles.

In theory it would work just like BIO-Spira...

I have a new 40g comming and Im thinking of floating a coupe bio-wheels from other tanks...squeezing filter juice in the tank from filter cartridges, and squeezing a sponge filter and then placing that same sponge filter within the tank.

 

[gfink]

This a great link, but my times were much longer.
http://www.drhelm.com/aquarium/Cycling.html

 

[TomK2]

Have you ever attempted to "seed" an aquarium?

in the past, yes - now I don't have another tank up and running. Had to start from scratch. I had fish in long before I ever heard testamonials of Bio-spira. Then I decided to make a project of it by keeping records. I am not sure I wanted to do B-S anyway, since I didn't want to buy all the fish at once. I have many LFS's, so I will probably pick and choose among the best as I shop around. Plus I just can't believe that you must have ammonia and nitrite spikes, so I am trying to figure what it would take, sans Bio-spira, to do this.

 

[TomK2]

This a great link, but my times were much longer.
http://www.drhelm.com/aquarium/Cycling.html

Another nice link. But notice how early the ammonia and nitrite peaks are? You went out to 5 weeks with no detectable levels. I am at 3 weeks. There has got to be some biofilter developement, or else there would have to be some ammonia, right? And if there is biofilter developement, why would a late spike occur if you didn't quickly up the bioload? I would love to figure this out. But I can't be certain I will stick to the protocol long enough.

 

[gfink]

There has got to be some biofilter developement, or else there would have to be some ammonia, right?

Maybe, maybe not.

A fish will always produce ammonia, but how long it takes before you can detect it is another story.
For example if you put one fish in a 10 gal tank, you may read 1 ppm ammonia after 10 days. (made up numbers) However, assuming the same rate of waste production, if you put the same fish in a 100 gal, you would only detect 0.1 ppm after 10 days. Now my test kit is capable of reading 0, 0.5, 1.0 ppm etc... so it would be 50 DAYS at this rate before I detected anything in a 100 gal tank.

Keep in mind that the ammnonia munching bacteria may not even bother to coloninze until your ammonia reaches a level that triggers the bacteria (sufficient food supply). If this is true, then there will aways be a distinct spike that can be approached slowly and safely. This value should be similar in every tank that takes a very low bio load approach. (FYI...Mine never climbed past 0.5 ppm.)

If the bio load is higher, it is easy to see how a higher spike would occur. Ammonia concentrations would be increasing faster than a reproducig colony could consume it. Eventually an equlibrium would be reached, but possibly at a higher concentration. Ammonia would fall and nitrites would then spike.

 

[TomK2]

Keep in mind that the ammnonia munching bacteria may not even bother to coloninze until your ammonia reaches a level that triggers the bacteria (sufficient food supply). If this is true, then there will aways be a distinct spike that can be approached slowly and safely

This would imply a "threshold" to stimulate bio filter growth. If so, then approaching it slowly means you will have the least overshoot when it is reached, but you must have overshoot. But then why wouldn't the bio-filter reduce when NH3 drops again below the threshold? Perhaps using the term "level of NH3 (ie: =ppm)" interchangeably with "amount of NH3 (= ppm x tank volume)" is the problem. Perhaps the rapid constant turnover of water through the filter can explain this? The LEVEL of NH3 is low, but since the water is passing through the filter 5 - 10 times an hour, the AMOUNT of NH3 seen by the filter is large, ie: 5 - 10 times the level ?

So, you spent 5 + weeks getting the growth threshold AMOUNT of NH3 (level of NH3 X your tank volume), your bio-filter grows, the NH3 level in the tank lowers, but the AMOUNT of NH3 that your bio-filter has to live on is "level of NH3 X volume through filter" which is adequate to sustain the filter?

Does this make any sense or am I just rambling? If this is anywhere close to the truth then it is pointless to continue with my experiment, since, no matter how slow or careful I am, I have to go through the toxin spikes. If that is so, I would conclude that Bio-spira is the way to go, even if I am going to slowly stock the tank over a month or two anyway(personal preference, I like to shop around and pick the best). I bet the folks at Bio-spira know the answer to this. If they are growing cultures of the bio-filter, they would know exactly what conditions are required for them.

 

[jsoong]

I don't think you should give up yet!

I don't normally work with bacteria, however, my understanding is that growth should be dependent on the amount of food ... & not necessarily the concentration. I suppose there will be a minimum concentration needed for the bacteria to extract the food, that concentration must be very low, otherwise all our bugs would die as soon as the level of NH3 crashes to unmeasurable at the end of cycling.

In this case, you would grow the amount of bacteria needed based on the total ammonia produced. The larger the tank volume (or conversely., the lighter the bioload), the lower the ammonia spike should be. So I would think it would be worthwhile to continue to see if this hypothesis is correct.

 

[TomK2]

The larger the tank volume (or conversely., the lighter the bioload), the lower the ammonia spike should be

My original hypothesis was actually that with the correct bioload, there would be NO ammonia spike. I was convinced that I was well on my way to showing this when gfink showed me the data from his trial. The bioload to tank volume ratio was nearly identicle to what I am doing. He had an ammonia and nitrite spike over five weeks out. I would have thought that if you could avoid an ammonia spike for 5 weeks, the biofilter would have developed enough to prevent it altogether. Of course, one trial does not prove all, so perhaps I may still be sucessful.

I can not think of any reason why there would be a threshold effect, like I discussed in my earlier post. I do know a bit about biology too. Yet that seems to be what Gfink saw in his tank. Of course, something else could have occurred that has not been taken into account. I think I will continue. I was planning to increase the bioload once nitrate was detected (5ppm lower test kit limit). I had guessed that this would occurr by 45 days. Like Gfink, if I make it to 45 days and everything is still zero I will need a lot of will power not to add more fish.

 

[jsoong]

He only saw a spike of 0.5 of NH3, that's not much of a spike & pretty safe for fish... certainly a lot less than 8 or 10 you see with traditional fishy cycling. So I think the low bioload approach is still beneficial.

Now, you might need to have a hugh tank volume to have no spike whatsoever. I remember reading about someone digging a 1/2 acre pond, and just throw in a bunch of koi, and had no "cycling" effect. But now a 1/2 acre pond is like a few hundred thousand gals ... a few order of magnitude larger volume than our tanks!

 

[TomK2]

I can not think of any reason why there would be a threshold effect

Uh oh. Now I CAN think of a reason for a threshold effect! Check out this link provided by fancyguppyguy:

http://article.dphnet.com/cat-01/naturewonders3.shtml

To summarize, dormant nitrosomas do react differently to different ammonia concentrations. 33 days and still no ammonia, nitrites, and nitrates. Might be wasting my time.

 

[TomK2]

SUCCESS !!!! Today I was able to detect nitrate at the lower test limit, 5 ppm. During the 40 days of the experiment, I never detected ammonia (total ammonia lower test limit of 0.25ppm) and never detected any nitrite (lower test limit 0.25ppm). I was gettting a little discouraged, especially since I was finding info as I went along that made me think that nitrosomas might not reactivate at low levels. Gfink's similar set up that went out 5 weeks before getting NH3 had me thinking that it couldn't be done. A summary is below:

55 gallon tank, two fluval 404 canister filters, Inline heater at 78 degrees 8-11 hours of tank light per day

Day 0 NH3=0, NO2=0, N03 = 0 six adult danios and four platies added
Day 12 everything still zero, pH 7.8 three more platies added
Day 34 everything still zero pH 7.8 some green-brown algae on fake plants
Day 35 everything still zero, pH 7.8 light tank vac and 15% water change

Day 36 everything still zero, pH 7.8 timid, poorly feeding platy can't be found. I DID NOT suck him up with the python! He was really freaked out by the vacuuming, hid for hours, I saw him one final time then he was gone. I figure he hid and died, other fish made short work of the remains.

Day 40 NH3=0, N02=0, N03=5ppm, pH 7.8 During the 40 days, about 6 grams of TetraMin tropical flakes (half a .42 Oz jar) was fed.

Contrary to popular advice, I did a light vac and water change before I had evidence of "cycle" completion because I just can't see why normal, quality tank husbandry shouldn't be done, and who would not vaccuum their tank for more than a month?

My conclusion is that using fish to establish a biofilter need not be cruel or put the fish in any stress or danger. A low bioload, with sparse feeding, and a hefty dose of patience (40 days worth!) can establish a biofilter. I arbitrarily chose the number of fish to be about one inch per 5 gallons or less. While I can say that this worked in a 55 gallon tank, smaller or larger tanks, or tanks with different filtration, might require a different bioload.

 

[gfink]

Congrats!

Now, I added about 2 fish per week to my tank after it cycled. I did not see any additional spikes.

BTW... I also had a bioload of about 1 inch of fish per 5 gal. In retrospec, it is amazing how much info you can find about cycling, but no info guiding you on how many fish you should use to start a new aquarium. I guess 1 inch per 5 gal is the new rule!

 

[jsoong]

Congrats! Tom.

I think you just established another way of fishy cycling, without harm to fish. If this can be replicated in other settings, it might be better than going fishless. I would rather see a few fish rather than an empty tank for a month.

 

[TomK2]

BTW... I also had a bioload of about 1 inch of fish per 5 gal. In retrospec, it is amazing how much info you can find about cycling, but no info guiding you on how many fish you should use to start a new aquarium. I guess 1 inch per 5 gal is the new rule!

You know, I could swear I was told this somwhere. I just now realized that I got the one inch per 5 gallon ratio as SW max bioload advice, and it had nothing to do with anything anyone said about FW starting. Still worked though! I would have to add that an inch of blood parrot is probably not the same as an inch of danio. perhaps the rule should be one danio or one platy per 5 gallons?

I would rather see a few fish rather than an empty tank for a month.

Which was the whole reason I was motivated to see this through!
I am really excited - I get to add more fish now! My wife wants some blood parrots. Think I could add two or should I be consdervative and add one this week and see how it goes?